Study says ultrasound images show even unborn babies yawn

Researchers from Durham and Lancaster Universities have discovered that ultrasound images show when a fetus is yawning and when it is just opening the mouth. This signals developmental market in the womb that will provide more information on the health status of the fetus.

The study on yawning as a developmental process was published in the international academic journal. 

The past studies by scientists have shown that fetuses yawn and other studies have stated that the unborn babies are only opening their mouths slightly and are not yawning. In the present study, the scientists completed 4D scans of 15 healthy unborn babies and the images show a clear difference between yawning and non-yawn mouth opening.

Dr. Nadja Reissland of the Department of Pyschology at Durham University said,  “The results of this study shows that yawning declines with increasing fetal age.” 

Based on the findings, the team of researchers believed that more than over half of the mouth openings found in the study could be considered yawns. 

The yawn studies were conducted with eight female and male fetuses during 24 to 26 weeks of gestation. While there was no major difference between yawning in males and females, yawning overall reduced following 28 weeks of gestation. 

The results of this study demonstrate that yawning can be seen in healthy fetuses and replicates previous studies with 2-D images.

Scientists are not sure as to the role of yawning, but believe that it may be related to fetal development. 

Mr. Nadja also said, “Given that the frequency of yawning in our sample of healthy fetuses dipped from 28 weeks to 36 weeks gestation, it seems to suggest that yawning and simple mouth opening have this maturational function early in gestation.” He also said, “Unlike us, fetuses do not yawn contagiously, nor do they yawn because they are sleepy. Instead, the frequency of yawning in the womb may be linked to the maturing of the brain early in gestation.”  

The researchers also said, more research is needed to identify how yawning can impact development in areas like central nervous system.